What about this question? It's discussing worm infections on a LAN rather than viruses but it's all malware at the end of the day. I've tried to edit my answer to the question to make a bit more broad in scope.

[How do I deal with the removal/eradication of an unknown worm on our network?][1]

If you're talking about individual machines in an individual context, as you mention *small* business, then SU may have some stuff that's more orientated towards that scale of things. A lot of our assumptions on SF about 'nuke from orbit' implicitly include the idea that the business will have some tools and procedures to make rebuiling a system 'low cost' compared to the time and effort taken to clean an infected machine and that might not be true for a small business.


  [1]: https://serverfault.com/questions/339552/how-do-i-deal-with-the-removal-eradication-of-an-unknown-worm-on-our-network